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Penmaenmawr · 08-01-2013, 10:06 PM

Took the 345 for a spin today after her long lay-up and recent work on brakes and suspension. She definitely was not completely happy, although she ran fine on the level she stuttered and misfired on part throttle accelerating or climbing slightly. Pushing the pedal to the floor she'd respond better, but the transmission didn't seem to want to kick down. I still think I have some water in my gas, having sat for 18 months or so, although I put alcohol in the tank.

The other thing that concerns me is that she seemed to run hotter than I remember (of course it was in early winter I drove her before) and the gauge stabilized around 205, but then climbed to 215 or 220 on steady climbs, and would rise even above 220 when I stopped again.... I put the radiator fans on manual, but they didn't pull the temperature back down as I expected. It was only about 72 degrees today.

I certainly wouldn`t trust her for a trip at the moment. Anyone have any thoughts about whether I`ve got one big or multiple small issues to deal with?

On the positive side, I was surprised to find the dash air works fine and blows cold!

bkahler · 08-02-2013, 03:00 PM

Just a thought, are you sure the fans were running?

If you haven't already you might also verify the level of coolant in the system. If it's low you will likely run higher temperatures.

It also sounds like your carburetor needs cleaning and/or rebuilt.

Oh yeah, one other thing. If the voltage to your dash instruments is running low then your temp gauge will read high. I see this all the time on our 310. When battery voltage is indicating closer to 12v the temp reads high, when the battery voltage is 13v or higher the temp drops.

Brad

**DKB_SATX** · 08-02-2013, 04:49 PM

No moho experience but general gearhead stuff... either a lean mixture or incorrect timing can make an engine run poorly and hot.

And running the dash air isn't doing any favors for your coolant temperature, since it contributes more load and if the condenser is ahead of the radiator, it increases the temperature of the air that makes it to the radiator, but I'm guessing at 72F you were just testing the AC, not running it during the drive. It's likely to be more than a month before I see temps that low at dawn!

Penmaenmawr · 08-03-2013, 12:21 PM

Quote:

Originally Posted by bkahler

Just a thought, are you sure the fans were running?

If you haven't already you might also verify the level of coolant in the system. If it's low you will likely run higher temperatures.

It also sounds like your carburetor needs cleaning and/or rebuilt.

Oh yeah, one other thing. If the voltage to your dash instruments is running low then your temp gauge will read high. I see this all the time on our 310. When battery voltage is indicating closer to 12v the temp reads high, when the battery voltage is 13v or higher the temp drops.

Brad

Thanks Brad. I had just checked coolant levels and topped up. PO had fitted a thin plastic container in place of the coolant tank, and that is leaking and must be replaced..... this seems to be another problem since I cannot find the correct tank.
Voltage seems fine, with 2 voltmeters fitted, both reading identically at 13.5-14v.

But the misreading gauge idea........hmmm. Fans were running when on Manual, but not on Auto. Maybe this does mean the gauge is out, since with the 345 standing idling and the gauge apparently showing well above 230, I'd expect the auto fan switch to be turned on. There was not so much as a downward budge in indicated temperature with both fans running. How could I check the true temperature? Buy another gauge?

The carb looks dirty indeed, and I was considering getting a rebuilt, then the aftermarket TBI idea kind of seized me, but if I could find a reasonably priced rebuilt it might be worth it. Can a person buy rebuild kits, or is that a "Don't even think about it" ?

Penmaenmawr · 08-03-2013, 12:27 PM

Quote:

Originally Posted by DKB_SATX

No moho experience but general gearhead stuff... either a lean mixture or incorrect timing can make an engine run poorly and hot.

And running the dash air isn't doing any favors for your coolant temperature, since it contributes more load and if the condenser is ahead of the radiator, it increases the temperature of the air that makes it to the radiator, but I'm guessing at 72F you were just testing the AC, not running it during the drive. It's likely to be more than a month before I see temps that low at dawn!

Thanks DKB_SATX (how is that pronounced?) Nothing should have changed on the timing since it ran fine, I don't think. Mixture problems are likely. I'm afraid I did have the AC running continually, until the temperature started to worry me that is, but I figure if it can't cope with 72 degrees with AC on then something needs fixing. 72 is pretty hot to me, I pass out at 80.

bkahler · 08-06-2013, 07:20 PM

Quote:

Originally Posted by Penmaenmawr

...But the misreading gauge idea........hmmm. Fans were running when on Manual, but not on Auto. Maybe this does mean the gauge is out, since with the 345 standing idling and the gauge apparently showing well above 230, I'd expect the auto fan switch to be turned on. There was not so much as a downward budge in indicated temperature with both fans running. How could I check the true temperature? Buy another gauge?

I bought a laser temperature probe similar to this one and use that for verifying temperatures on just about everything. I was able to verify that even though the temp gauge was reading 205-210 the outlet from the engine feeding the radiator was only running 185-190.

I pretty much use the dash gauge to monitor temperature spikes such as when towing up a hill. I only really get concerned if the temperature goes up and doesn't seem to want to come back down to where it was.

Brad

Penmaenmawr · 08-06-2013, 08:48 PM

Quote:

Originally Posted by bkahler

I bought a laser temperature probe similar to this one and use that for verifying temperatures on just about everything. I was able to verify that even though the temp gauge was reading 205-210 the outlet from the engine feeding the radiator was only running 185-190.

I pretty much use the dash gauge to monitor temperature spikes such as when towing up a hill. I only really get concerned if the temperature goes up and doesn't seem to want to come back down to where it was.

Brad

Thanks Brad.... Free shipping from that site too! I just ordered one.

I have found several sites with Rochester Quadrajet rebuild kits. Reputation-wise I think maybe it reduces to Mike's Carbs (carburetor-parts.com) and quadrajetparts.com, but everywhere seems to be in the high 20's to low 30's price-wise. A couple of useful how-to sites:
Rebuilding a Rochester QuadraJet Carburetor | Generation: High Output
and
Ken's QuadraJet
with plenty of pictures (I need those, plus larger print.....)

Looks a lot more complicated than a Zenith, Solex or SU rebuild, of the kind I've done before, but worth a try before spending 400 bucks on a rebuilt.

Penmaenmawr · 08-24-2013, 01:28 PM

Well, I got the laser temperature probe, as recommended by Brad. Just like the picture on eBay, and works just fine. Now I know the temperature of everything around the house, walls, fridge, windows, dog butts. Do you know a Jack Russell has an internal mouth temperature of 100.8 degrees? My wife is a little sick of this however, and it only arrived yesterday. I can see her thinking she's about to help me take internalo rectal temperature with it if I don't quit pretty soon......

Back to the 345 though. I took her for a 10 mile ride in 78 degree heat, dash AC running all the time to speed up the engine warming. By the end (as the pictures hopefully show) the dash gauge showed about 225 degrees, and by carefully aiming at the visible corners of the radiator, I got these temperatures:

Passenger top 185 Driver top 208.5
Passenger bottom 84.5 Driver bottom 202

.... all degrees Fahrenheit. And yes I was careful on the passenger bottom, and it stayed right at that much lower temperature during the ride (I stopped midway to check temps).

I lifted the doghouse cover, and there was nothing superhot on the engine/air cleaner etc.

I'd be interested in the comments of those more familiar with these things than I am.

Naper · 08-24-2013, 01:33 PM

What is the temp. of the top rad hose and bottom rad hose ?

bkahler · 08-24-2013, 02:45 PM

Hmm, I guess I'm not the only one that checks the temperature of everything in sight

For temperature locations I always do what Naper said. Shoot the radiator hose where it comes out of the top of the intake manifold up front (I believe this is where the coolant exits the block going to the radiator) and the bottom hose where it enters the radiator which should be the cooled coolant coming from the radiator).

Brad

bkahler · 08-24-2013, 02:48 PM

On a similar topic, I took the temperature sender from the block of the 345 I dismantled and connected it to the 345 temperature gauge. I put the sender in a pot of water that I slowly brought up to boiling and didn't temperature readings that made any sense. I'm not sure if this means the gauge is bad, the sender is bad or what. Once I start my Argosy engine up again on the engine stand I'm going to do some more testing with the 345 gauge to see if I can determine just how accurate it is.

Brad

Penmaenmawr · 08-24-2013, 03:09 PM

Quote:

Originally Posted by Naper

What is the temp. of the top rad hose and bottom rad hose ?

Ooops..... guess I was too lazy or stupid to take those.... I was thinking the top driver side would be much the same as the top hose and bottom passenger side be about the same as the bottom hose. I think I checked the top hose half way round the trip and it was 190-ish when the top driver side of the radiator was about 199. But I didn't take a picture to remind me. The temp gauge showed 220 by that point in the trip.